Method of making lock-seam tubing.



F. KRITZ. I METHOD OF MAKING LOCK SEAM TUBING.

APPLICATION FILED .IUNE 29.1916.

1 ,Q63,3Q Patented Apr. 16, 1918.

' FRANK, Kan-z. y 3; m m9 gr flTTozNE 6 state, but in Fig. 1, I

, provide a method I in continuous lengths 'vention may be used.

D STA J; PAT

FRANK or nnmorr,

STANDARD PARTS COMPANY, OF CLEVELAND, OHIO, A CORPORATION OF OHIO.

METHOD OF MAKING LOOK-SEAN TUBING.

Specification of Letters Patent.

Patented Apr. 16, 1918.

A Application filed June 29, 1916. Serial N 0. 106,554.

To all whom it may concern:

Be it known that I, FRANK Kurrz, a citizen ofthe United States, and aresident of Detroit, county of Wayne, and State of Michigan, haveinvented a new and useful Improvement in Methods of Making Lock- SeamTubing, of which the following is a pecification, the principle of theinvention bein herein explained and the best mode in whidh I havecontemplated applying that principle, so as to distinguish it from otherinventlons.

The present improvements, indicated, to the manufacture of so-calledlock-seam tubing, have more special regard to the manufacture of tubingof this sort, which is characterized by having a longitudinallyextending channel or groove in one side. Tubing of this form has foundan extended field of use in the manufacture of wind shields forautomobiles and in other similar connections, the aforesaid channelbeing adapted to receive the pane of glass forming the shield proper.

One object of the present invention is to for forming such tubing out offlat strip stock with channel complete, so as not to require anysubsequent manipulation inorder to produce such channel. Another objectis to avoid the necessity of using a mandrel in the formation of thetubing. By my present improved method, moreover, I secure an extremelystrong and efficient lock-seam. To theaccomplishment of the foregoingand re lated ends, the invention, then, consists of the stepshereinafter described and particularly pointed out in the claims, theannexed drawing and the following description setting forth in detailone carrying out the invention, such disclosed mode constituting,however, but one of various ways in which the principle of theinrelating as In said annexed drawing The several Figures 1 to 7inclusive, represent in cross-section, a strip of stock in varioussuccessive stages of manufacture into channeled lock-seam tubing,according to my improved method or process of manufacture.

It has not been deemed necessary in connection with the foregoing seriesof figures to illustrate the flat stock in its original Y show theresult on the approved method of body 1 of such, stock of the first stepof the operation, such step consisting in turning up two, similarlydirected angular flanges 2 and 3 the strip. Of such two flanges, theportions 4 and 5 adjacent the body 1 of the strip, which still remainsflat or straight in crosssection, are of substantially equal width,while the angularly related portion 6 of the flange 3, the one on theright-hand side in the figure in question, is, somewhat wider than theother, and wider than the bottom of the prospective groove or channel.The outer edge 7 of such angularly related portion, is furthermorelightly bent up at this stage, preliminary to forming thereof, insuccessive tages, a recurved hook which forms part of ,the lock-seam.

In the second and third stages of the operation, as illustrated in Figs.2 and 3 respectively, the formation of the flanges is carried on and inaddition the body of the strip is by degrees given a curvedcross-section.

In the fourth stage, as illustrated in Fig. 4, such cross-sectionbecomes practically semi-circular in form, and both flanges aresubstantially complete in themselves, although not bent inwardly withrespect to the body of the strip into the'positions which they arefinally required to assume.

The next two steps, illustrated in Figs. 5 and 6, respectively, consistin bending the angular flanges 2 and 3 inwardly, the latter flange,carrying the angularly related portion 6 that constitutes the bottom ofthe channel, being turned in in advance of the former flange, so thatsuch flange 3, when brought down into more or less radial position withrespect to the central axis of the tube, will engage with its a'ngularlyrelated portion 8, the recurved, hook-like edge 7 of the angularlyreated portlon 6 of such flange 2. When, accordingly, said flange 2 isforced .o'ver toward the left,'that is, away from the side 5,theinter-engagement or locking of its angularly related portion, with there-curved portion of the flange 3, will be complete, and the seam thusfinished simultaneously with the MICHIGAN, ASSIGNOR, IBY MESNEASSIGNMENTS, TO THE on the respective edges of that one portion of eachflange constitutes the respective side-walls, and the angularly relatedportion 6, of flange 3, the bottom of the channel, the flangeportion 6overlying the angularly related portion 8 of the vother flange, andbeing recurved at its edge 7 so as to interlock therewith at one side ofsuch channel. 7

All of the several stages illustrated my improved-vprocess, may beconveniently and atisfactorily carried outv by the use of forming rolls,as need not be explained in detail in the present connection, such rollhavlng their peripheral faces of proper shape in cross-section to impartto the original plain strip the several different cross-sec tional formsillustrated in the figures, and no mandrel being needed.

It will be understood that it is of course a vmatter of indifferencewhether the complete operation be divided up into the exact number ofsteps thus illustrated, or that the strip be left in precisely the formillustrated after each of such successive operation.

Other modes of applying the principle of my invention may be employedinstead of body of the strip transversely so as to bring the edges-ofsuch flanges together.

2. The method of making channeled lockseam tubing, which consists informing similarly directed, angular, flanges on the respective edges ofa strip of stock, the edges of such flange-portions being formed forinterlocking engagement; and then bendin the body of the striptransversely so as to ring the edges of such flanges together, the mainportions of such flanges constituting the respectlve s de-Walls, and theangularly related portion of one flange, the bottom, of the channel inthe completed tubing.

' 3. Themethod'of making channeled lockseam tubing, which consists informing similarly directed, angular flanges on the respectwo edges of astrip of stock; recurving the edge 0 the angularly related portion ofone -such flange and then bending the body of the strip transversely soas to bring the other angularly related flange-portion into engagementwith such recurved edge, the mam portions of such flanges constitutingin the [manufacture of tubing in accordance with naoasas the respectiveside-walls, and such angularly related portion with recurved edge, thebottom, of the channelin the completed tubing.

4:. The method of making channeled lockseam tubing, which consists informing flanges on the respective edges of a strip of stock, suchflanges each comprising a main portion and a portion disposed atapproximately right angles thereto; recurving the edge ofthe-angularlyrelated portion of one such flange; and then'bending the body ofthestrip transversely so as to bring the other angularly relatedflange-portion into engagement with such recurved edge, the mainportions of such flanges constituting the respective side-walls, andsuch angularly related portion with recurved edge, the bottom, of thechannel in the completed tubing.

5. The method of making channeled lockseam tubing, which consists informing flanges on the respective edges of a strip of stock, suchflanges each comprising a main portion and a portion disposed at,approximately right angles thereto, the angularly related portion, ofone flange being wider than the other; recurving the edge of suchlast-named flange-portion; and then bending the body of the striptransversely, so as to bring the other angularly related flange.

portion into engagement with such recurved edge, the main portions ofsuch flanges constituting the respective side-walls, and such wider.angularly related flange-portion with recurved edge, the bottom, of thechel in the completed tubing.

6. The method of making a channeled lock-seam tubing, which consists informing angular flanges on the respective edges of a strip of stock,bending the body of the strip transverselyso as to bring the mainportion of such flanges in parallel relation, but spaced apart adistance approately equal to the desired width of channel; andinterlocking the respective edges of such flanges to form a lock-seam.

7. The method of mag a channeled lock-seam tubing, which consists informing angular flanges on the respective edges of a strip of stock,bending the body or the strip transversely so as to bring themainportions of such flanges in parallel relation, but spaced apart adistance approximately equal to the desired width of channel; andinterlockingthe respective edges of such flanges to form a lock-seam atthe one bottom corner of such channel.

8. The method of making channeled lockseam tubing, which consists informing on one edge of a strip of stock an angular flange, the mainortion out which constitutes the side wall 0 angularly related portionof which constitutes the bottom of such channel; forming a flange on theother edge of such strip of stock, which constitutes the other side walll Sill the desired channel, the

of such channel; bending the body of the -strip transversely so as tobring the main portion of such first flange and said second flange inparallel relation, but spaced apart a distance approximately equal tothe desired width of channel; and inter-locking the respective edges ofsuch flanges to form a lock-seam.

9. The method of making channeled'lockseam tubing, which consists informing on one edge of a strip of stock, an angular flange, the mainportion of which constitutes the side wall of the desired channel, theangularly related portion of which constitutes the bottom of suchchannel; recurving the edge of such angularly related flange portion toconstitute a lock; forming on the other edge of such strip of stock anangular flange, the main portion of which constitutes the other sidewall of such chalmel, the anwidth of channel; and simultaneouslyinterengaging such tongue and lock so as to form a lock-seam at the onebottom corner of such channel.

Signed by me, this 24 day of J1me 1916.

FRANK mrrz. Attested by M. H. Wmnmms, C. J. Sm'rn.

